U.S. rates of heterosexually transmitted HIV infection are dramatically higher among AAs than Whites. Concurrent partnerships (sexual partnerships that overlap in time) speed transmission of HIV through sexual networks much more effectively than does serial monogamy with the same total number of sexual partners and are more common among AAs than Whites. Recent mathematical simulations demonstrate that small decreases in the prevalence of concurrent partnerships can result in marked changes in population HIV transmission. Although successful control of the US HIV epidemic will ultimately require attention to the powerful contextual forces that promote AAs' high concurrency rates, there is an urgent need for behavioral interventions that reach large groups of people to promote safer sex practices and change adverse sexual network patterns. The goal of this research is to develop effective mass media messages and strategies to decrease HIV transmission among AAs by reducing concurrent sexual partnerships. We will conduct qualitative and quantitative research among AA men and women, ages 18-34, in 7 eastern North Carolina counties to: 1) Construct prevention messages and communication strategies that target participation in concurrent partnerships. 2) Work with an established communications firm to design and implement a culturally competent eight-month mass communication campaign that informs AAs about the relationship between concurrency and HIV dissemination and decreases their willingness to participate in this network pattern. 3) Evaluate the campaign's effects on AAs' attitudes, beliefs, and norms about concurrency, reported participation in concurrent partnerships, and reported condom use through the conduct of phone surveys among 600 men and women before and after the campaign. This research represents a critical first step in the development of a mass media campaign that will play a key role in a multi-component HIV prevention program for AAs in the rural Southeastern US and throughout the nation.